Today i just bought some PNY ram, I'm not sure what model it is but it's a single 4GB ram stick. I added it to my system that already has Mushkin Blackline ram in 2x2GB. Everything seemed fine so I went onto World of Warcraft and I was playing for close to 30 minutes when my game froze and then I was notified that my Display Drivers stopped working. ( I have a AMD XFX 6870. ) I took note of it and carried on playing. After another 10 minutes it crashed again but this time It went onto the blue screen of death, on it it mentioned that the display drivers crashed and failed to respond. Can someone please help me out here?